# Kenetic Theory of Gas

1. May 5, 2009

### hatcheezy

1. The problem statement, all variables and given/known data
The mass of a single HE atom is 6.65e-27kg. You have 5.00e-6 mole of HE gas which is occupying a volume of 1.00e-4m^3. when at pressure of 100Pa. Determine the temp of gas AND the average speed of the gas molecules.

**I've found the temp of gas i need help on the avg speed - i believe i'm close
2. Relevant equations
Vrms=$$\sqrt{3(R)(T)/(M)}$$

3. The attempt at a solution
Vrms=$$\sqrt{3(8.31J/mol K)(241)/(6.65e-27kg????)}$$

i'm not certain if i use 6.65e-27kg as molar mass?

2. May 5, 2009

### RoryP

Note it gives you the mass of a single atom

This is the amount of moles present

After reading the above do you still think this?

3. May 5, 2009

### RoryP

ahh i do apologise i had not realised you have calculated the temperature, please ignore the post above